Population justification: The breeding population is estimated to number 24,600 pairs, based on surveys from 1995-1997.

Trend justification: Numbers decreased steeply in the 1970s and 1980s, attributed to bycatch longline fisheries. One colony declined at a rate of 5.9% per year between 1966 and 1981, and 10.5% per year between 1981 and 1984, equating to an overall population reduction of 72% during that period. However, numbers have been either stable or increasing slightly since 1984 (Waugh et al. 1999a), with a 1.8% increase recorded in selected colonies between 1992 and 1997 (Moore 2004), although the last census was in 1996/7. The trend over the past three generations (85 years) is assumed to be negative, but, based on the decrease in fishing effort following a peak in 1971-1983, the population is considered likely to continue to expand.

Recommended citation
BirdLife International (2015) Species factsheet: Thalassarche impavida. Downloaded from
http://www.birdlife.org on 31/03/2015.
Recommended citation for factsheets for more than one species: BirdLife International (2015) IUCN Red List for birds. Downloaded from
http://www.birdlife.org on 31/03/2015.

This information is based upon, and updates, the information published in BirdLife International (2000)
Threatened birds of the world. Barcelona and Cambridge, UK: Lynx Edicions and BirdLife International, BirdLife International (2004)
Threatened birds of the world 2004 CD-ROM and BirdLife International (2008) Threatened birds of the world 2008 CD-ROM. These sources provide the information for species accounts for the birds on the IUCN Red List.

To provide new information to update this factsheet or to correct any errors, please email BirdLife